Oracle and SAP continue to disagree over a $1.3bn damages fee that the former claims it is owed for the theft of software by a now-defunct subsidiary of SAP called TomorrowNow.
The two firms have been tussling in the courts for over five years after Oracle accused the TomorrowNow subsidiary of stealing code from its products that were then used in services it sold to SAP customers.
Although SAP acknowledged this had taken place and agreed to pay damages, the total cost of the copyright infringements has still not been settled.
Initially, back in November 2010 SAP was ordered to pay Oracle huge damages of $1.3bn, but this was reduced to $272m on appeal.
Oracle was unhappy with this and said it wanted a retrial. In response, SAP offered to pay $306m and Oracle's legal bill of $120m. But Oracle said this was still not enough and sent the decision to appeal.
However, Oracle does not seem to have received the backing it was hoping for. Judges at the US Court of Appeals in San Francisco questioned whether the $1.3bn amount - originally selected by a jury - was a fair reflection of the infringement, according to a report on Bloomberg.
Circuit Judge Susan Graber was reported to have said that she did not think the revenue estimates provided "suggest anything about what the licence might have cost. Even if it was objective, my concern is that it's evidence of something else."
US Circuit Judge William Fletcher added: "This may be sort of pie in the sky, dreaming. There are a lot of variables in there that make it somewhat speculative."
None of the judges on the case suggested a figure that they believe would accurately reflect the copyright theft, opening up the possibility for a retrial to try to determine a figure both sides would accept, reported Associated Press.
Oracle said it had no comment on the case while SAP said it hoped a resolution would be found.
"We are gratified that the Court was engaged and interested in the issues, and we look forward to the Court's decision bringing us closer to resolving this case," it said.
The legal drama comes in the same week that Oracle won a key round in another high-profile case, this time against Google.
The US Court of Appeal in Washington ruled that Java software used in Android could be considered copyrighted, opening up the possibility of Oracle winning damages in excess of $1bn from Google.
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